This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The aim of the CHARTER Program is to examine the evolving nature of neuroAIDS, particularly with modern HIV medication use. The study was designed as a 5-year program (2002-2007) with a 3-year extension (2007-2010). This three year period was seen as an opportunity to gather additional data. The Investigators are interested in learning more about HIV-associated neurological disease and will collect detailed medical, laboratory, psychological and psychiatric histories and evaluations over the next 3 years on approximately 300 people, every six months at the 6 sites. This information will help them understand if and how anti-retroviral medications (HAART) affect the complication or prevention of neurological disease and impairment (such as dementia or peripheral neuropathy) in those infected with HIV. Researchers are also interested in the effect HAART has on the metabolic changes that often occur, i.e., loss of or redistribution of body fat. A secondary concern is how HAART and psychiatric medications interact. Study participants will be asked to undergo testing every 6 months. Basic testing will include neurological examination, neuropsychological evaluation, psychiatric history, blood collection, and a lumbar puncture. Additional testing may include nerve conduction studies, quantitative sensory testing, MRI, and or skin biopsy.